Is Everything Determined?

[smack Down]

Originally posted by: suszterpatt
Two words: butterfly effect.



Any restricted prediction we make will be thrown off by the things we chose to ignore in the calculations. And since the universe is infinite, I don't think there can be an equation that takes absolutely everything into consideration.

The butterfly effect is based in chaose theory and based on using numerical differentintion instead of an exact version. What happens is small errors from having a step size less then 1/infinite create a great change in the output so even if you knew the exect value for every variable you still would be limited to how far in the future you can predict.

 

[Smilin]

Originally posted by: smoaky
whoa, I think you misread me, I meant that as a lighthearted comment. I mean I do essentially believe it, but I'm not "close minded". The thread starter asked for our opinions... My post may be a bit of a downer, but if you let it get to you that much, thats not my problem.


Edit - But obviously, my beliefs don't get in the way of performing my everyday tasks, otherwise I'd go crazy.

No worries, I feel you.

 

[f95toli]

Originally posted by: smack Down

Originally posted by: networkman
I was also just thinking about "Heisenberg's Uncertainty Principle" and that it might well apply in a slightly different way.. that way being that we could probably design equations to increasingly more accurately predict future events, but never be all-encompassing enough to exactly predict every event.

The uncertainty principle states that you can't know both the current position and velocity of an electron because any measurement of it will change one or both it doesn't put any limits on having a forumal that can predict the future position of the electrion if you know its current position and velocity.

That is not exactly correct. The uncertainty principle itself does not say anything about "measurments", it is a relation between the commutator of two conjugate operators and the uncertainty of the expectations values of those operators. In its simplest form it reduces to the xp-uncertainty you refer to.
However, the uncertainty principle itself is just a consequence of the basic rules of quantum mechanics and in the precense of dissipation many systems are truly stochastic. One example is macroscopic quantum tunnelling (MQT) which is a process which is extremely well understood. However, we still can only predict statistical properties of of a system which is in the MQT regime, because MQT is a "random" process on a fundamental level. Hence, if you tell me e.g the temperature and a few other parameters I can tell you what the disitribution will look like if we repeat the experiment 10 000 times but I can't predict the outcome of a single experiment. Note that the measurment process itself is not the reason for the "unpredictability" in this case, the reason is that after the tunnelling event the system enters a dissipative regime whcih is irreversible.

 

[CycloWizard]

Originally posted by: smack Down
The butterfly effect is based in chaose theory and based on using numerical differentintion instead of an exact version. What happens is small errors from having a step size less then 1/infinite create a great change in the output so even if you knew the exect value for every variable you still would be limited to how far in the future you can predict.

Not exactly. Chaos theory generally states that, while we can theoretically exactly describe the behavior of a system using certain equations (e.g. Navier-Stokes equations), any infinitesimal change in the initial conditions of the system may have drastic effects on the outcome. The most common example is weather. Everything about the weather can be determined by solving the conservation equations for mass, momentum, and energy simultaneously. However, since we cannot accurately define the initial conditions or disturbances in the system (e.g. a butterfly flapping its wings, changing parts of the momentum and energy equations), we can only predict the outcome within certain limits. This is why multiple possibilities are shown for the path of a hurricane instead of a single, definitive path.

 

[suszterpatt]

Originally posted by: CycloWizard
Not exactly. Chaos theory generally states that, while we can theoretically exactly describe the behavior of a system using certain equations (e.g. Navier-Stokes equations), any infinitesimal change in the initial conditions of the system may have drastic effects on the outcome. The most common example is weather. Everything about the weather can be determined by solving the conservation equations for mass, momentum, and energy simultaneously. However, since we cannot accurately define the initial conditions or disturbances in the system (e.g. a butterfly flapping its wings, changing parts of the momentum and energy equations), we can only predict the outcome within certain limits. This is why multiple possibilities are shown for the path of a hurricane instead of a single, definitive path.

And since we can't determine the properties of every single particle in the universe (due to it being infinite and all), we can never come to a prediction that won't prove wrong after a certain amount of time. Even if we could, it would only work for inanimate objects and perhaps very low level lifeforms. We'd need to figure out how exactly the brain works before we could apply particle-based predictions to humans.

 

[MAW1082]

So later on in this speech, Hawking discusses why he thinks people believe in free will:

He thinks it's an evolutionary advantage for one to believe that they can change the outcome of the future. Those who believe the future is already determined will not stock food for the winter, prepare for a catastrophe, etc.

I presonally find this a very convincing argument. There MUST be a set of laws which describe the interaction of all particles. If we discover this law and subsequently apply it to a perfect map of the universe then we would be able to see the future. But by seeing the future, could we change it? The answer is NO, because the equation would have already 'taken into account' that we would see the future.

It's a paradox. "Everything is determined, but it might as we not be because we will never knwo what is determined!"

 

[rocadelpunk]

i dunno...we could divide by 0 and really fvck with the equation

wonder if it equals 42.


and I don't think knowing the equation would disable us from changing the future.


even if everything was accounted for I don't believe there would be one pinpoint answer to whatever it was you were solving for...there'd be multiple (maybe millions) of valid solutions. I actually don't see how it'd change many things...unless we'd be able to figure out what happened in the first min of universe as opposed to 1 min and everything after.

 

[CycloWizard]

Originally posted by: MAW1082
So later on in this speech, Hawking discusses why he thinks people believe in free will:

He thinks it's an evolutionary advantage for one to believe that they can change the outcome of the future. Those who believe the future is already determined will not stock food for the winter, prepare for a catastrophe, etc.

I presonally find this a very convincing argument. There MUST be a set of laws which describe the interaction of all particles. If we discover this law and subsequently apply it to a perfect map of the universe then we would be able to see the future. But by seeing the future, could we change it? The answer is NO, because the equation would have already 'taken into account' that we would see the future.

It's a paradox. "Everything is determined, but it might as we not be because we will never knwo what is determined!"

If there is some magic 'brainitron' (a particle in the brain that controls our thoughts ), then the equation could predict our behavior. However, as yet, the nature of 'consciousness' is undetermined in that it has not been linked to anything physical.

In any case, we could never really know whether Hawking is correct or not. We could never determine whether we cause our brains to behave as we see fit or if we 'see fit' because our brains behave that way.

 

[MAW1082]

Originally posted by: CycloWizard

Originally posted by: MAW1082
So later on in this speech, Hawking discusses why he thinks people believe in free will:

He thinks it's an evolutionary advantage for one to believe that they can change the outcome of the future. Those who believe the future is already determined will not stock food for the winter, prepare for a catastrophe, etc.

I presonally find this a very convincing argument. There MUST be a set of laws which describe the interaction of all particles. If we discover this law and subsequently apply it to a perfect map of the universe then we would be able to see the future. But by seeing the future, could we change it? The answer is NO, because the equation would have already 'taken into account' that we would see the future.

It's a paradox. "Everything is determined, but it might as we not be because we will never knwo what is determined!"

If there is some magic 'brainitron' (a particle in the brain that controls our thoughts ), then the equation could predict our behavior. However, as yet, the nature of 'consciousness' is undetermined in that it has not been linked to anything physical.

In any case, we could never really know whether Hawking is correct or not. We could never determine whether we cause our brains to behave as we see fit or if we 'see fit' because our brains behave that way.

The atoms, molecules, and chemicals in our brains behave according to physics. There is no question about that. The problem is that there is such a large number of these atoms, molecules and chemicals that it is currently impossible to apply physics to the human mind. The human body is a very complex machine, nothing more.

 

[CycloWizard]

Originally posted by: MAW1082
The atoms, molecules, and chemicals in our brains behave according to physics. There is no question about that. The problem is that there is such a large number of these atoms, molecules and chemicals that it is currently impossible to apply physics to the human mind. The human body is a very complex machine, nothing more.

Since you nor I knows the physical/metaphysical origin of consciousness, to assume that it's linked to some physical process is simply begging the question.

 

[suszterpatt]

Originally posted by: MAW1082
[The atoms, molecules, and chemicals in our brains behave according to physics. There is no question about that. The problem is that there is such a large number of these atoms, molecules and chemicals that it is currently impossible to apply physics to the human mind. The human body is a very complex machine, nothing more.

The problem is not their number. Hell, by claiming that we can "predict anything", we're already assuming that we can determine the state of every single particle in the universe in an instant.


The problem is that we don't know how these particles build up consciousness, thoughts, feelings and all that jazz. When (if at all) we discover how the change of a particle can alter the thoughts of a human, then we can think about predicting things based on how particles follow the laws of physics.

 

[CSMR]

Originally posted by: MAW1082
Hawking's general ideas:

There is a set of equations that if found can predict the outcome of any system . . . unification

What if we find the set of equations:

a. We'll be able to predict to the future

b. But by being able to predict the future, we could change it

Thus, he concludes that we could never find the exact set of equations to predict the outcome of 'our' system

So, Hawking thinks that 'everything is determined, but it might as well not be because we could never know what is determined!'

What do you think?

What he is saying is at best trivial and at worst confused. Imagine that the set of equations did not have to be comprehensible. Then we could have an infinite set of binary equations (quite a large infinity) each one corresponding to one aspect of the physical world (that is, to one aspect of sense perception). It is trivial then that such a set of equations exists. On the other hand if he means by "a set of equations" a finite mathematical forulation which tells us what happens in the universe then as time goes on we can approximate to a belief in the true set of equations by baysian updating on a prior with positive probability on each finite mathematical formulation. (More precisely if we restrict interest to the set of measurements in the past and future. Obviously things happened in the past which we do not know and so no amount of measuring in the present and future can tell us what happened then.)

The argument against our knowing everything about the universe seems like a potentially fruitful one.

 

[CSMR]

Originally posted by: DrPizza
Just a thought -
If Hawking is correct, doesn't that mean that there actually isn't free-will?

I don't know if it does but...

And, doesn't that undermine some of the religions?
And, isn't Hawking bent on proving the non-existence of God?

/end just a thought.

In England everyone tends to believe in free will whether atheistic or theistic. And God certainly doesn't imply free will, as Lutheranism and Calvinism for example show.

 

[CSMR]

Originally posted by: MAW1082
So later on in this speech, Hawking discusses why he thinks people believe in free will:

He thinks it's an evolutionary advantage for one to believe that they can change the outcome of the future. Those who believe the future is already determined will not stock food for the winter, prepare for a catastrophe, etc.

This also happens in England, that natural scientists are given authority to speak out on any subject however ignorant they are about it. In this case Hawking mouths off on free will without understanding that choice does not imply free will. He has read in a book perhaps that free will conflicts with determinism (as it does) and then assumed that free will is the ability to choose, and then concluded that determinism is in conflict with the ability to choose. Then he says determinism means we can't choose anything and he is held up as an insightful thinker when all he has done is made a hash of issues that were quite well argued and even understood several centuries ago.

 

[bendixG15]

that natural scientists are given authority to speak out on any subject however ignorant they are about it.

Not only England, but here on AT.....

 

[Velk]

Originally posted by: CycloWizard

Originally posted by: MAW1082
So later on in this speech, Hawking discusses why he thinks people believe in free will:

He thinks it's an evolutionary advantage for one to believe that they can change the outcome of the future. Those who believe the future is already determined will not stock food for the winter, prepare for a catastrophe, etc.

I presonally find this a very convincing argument. There MUST be a set of laws which describe the interaction of all particles. If we discover this law and subsequently apply it to a perfect map of the universe then we would be able to see the future. But by seeing the future, could we change it? The answer is NO, because the equation would have already 'taken into account' that we would see the future.

It's a paradox. "Everything is determined, but it might as we not be because we will never knwo what is determined!"

If there is some magic 'brainitron' (a particle in the brain that controls our thoughts ), then the equation could predict our behavior. However, as yet, the nature of 'consciousness' is undetermined in that it has not been linked to anything physical.

Given documented evidence that physical processes can lead to lack of consciousness it seems a reasonable premise to work from. Is there much support outside of religious circles for a non-physical answer ?

 

[Velk]

Originally posted by: DrPizza
Just a thought -
If Hawking is correct, doesn't that mean that there actually isn't free-will?
And, doesn't that undermine some of the religions?
And, isn't Hawking bent on proving the non-existence of God?

/end just a thought.

Yes*.
Yes.
I doubt that is his motivation.

* In an absolute sense, but the practical implications of that are not really significant. Take computers and random numbers for example - the knowledge that a given random number *could* be related back by a fixed process to a known set of seed parameters doesn't actually do much to change it's perceived randomness.

In the same way, even if it was known for certain that someone who knew the position and state of every subatomic particle in the universe and the formula's for their interfaction could accurately predict whether you were going to decide to buy chocolate or vanilla ice cream at the supermarket doesn't really have any impact on your day to day life.

 

[LumbergTech]

i think that everything is determined in the sense that there are laws of the universe which constrain us into acting a certain way..i am not sure if we have what you would call micro-choices (a little bit of leeway) within the constraints or not ........it sort of reminds me of algebra.. within a linear equation..you can go in either direction infinitely but you are still stuck w/ the same slope (hopefully i didnt just butcher that concept)